There were 135 PubMed-indexed Studies about SARMs (steroid androgen receptor modulators) at the end of January 2019.

SARMs were a hot topic in American Society of Bone and Mineral Research conference held in Quebec, Canada. The established technologies for improvement of bone function are high dose vitamin D, bisphosphonate drugs and somewhat more novel combination therapy of monoclonal antibodies that attack osteoclasts (cells that normally remodel the bone but cause osteoporosis if their proportion is out of balance) and recombinant parathyroid hormone that supports osteoblasts (bone-building cells) if used intermittently [1]. However, the SARMs were the most interesting from the novelty perspective.

A really interesting study published in 2019 discusses a SARM found from the nature (wild bitter gourd extract) and compared the SARM with testosterone in castrated mice (to unmask the effects of treatment from endogenous male steroid hormones). While testosterone increased the mass of both muscles and male accessory glands (prostate and seminal vesicles), the bitter gourd extract increased grip strenth and acrobatic/balance performance measured with as measured by the typical rotarod test [2]. Boosting mitochondria and their oxidative capacity as well as negating castration-induced muscle decline was proposed as mechanism of action.

A review paper was also published in 2019. It is somewhat a non-news that no SARMs are available as prescription drugs. In summary, the research has found that these molecules seem to have few if any drug interactions and the clinical studies suggest potential future applications for pathological muscle loss, benign prostate hyperplasia (BPH), hypogonadism and breast cancer [3] as well as, possibly, Duchenne muscular dystrophy (a disease which causes progressive weakness of muscles that is eventually lethal due to withering of breathing muscles). In contrast to uses related to disease, the use of SARMs as performance-enhancing agents was briefly discussed, as these drugs have anabolic effects with less side effects (without excluding potential for abuse), that make SARMs interesting for bodybuilding community.

In addition to regular additions to the set of studies dedicated to development of methods of doping detection, a few other studies were published in 2018: development of transdermal system of administration of SARM LY305 [4] – it improved the speed of muscle and bone repair without overt adverse effects in laboratory rodents, and was well-tolerated in human volunteers. Another study discovered that SARM S42 inhibited proliferation of prostate cancer cell line PC-3 [5]. Third study, expectedly, found that YK11 supported the function and proliferation of bone-building osteoblast cells of mice [6], and another study weighed in additional evidence by showing the anti-osteoporosis effects for the currently perhaps the best-known SARM ostarine [7].

Animal studies (especially optimistic ones for the sake of caution) must be taken with a grain of salt, though. A study found that LGD-4033 (that may also be known as ligandrol) metabolizes moderately differently in humans and horses, which adds a layer of complexity to interpretation of animal studies in general as well as doping detection in different species specifically [8].

While the aim of this text was to summarize the studies published in 2019 and 2018, a few studies of interest were published in 2017 deserve mentioning. We will cover this in future posts.

[1] https://www.ncbi.nlm.nih.gov/pubmed/30590370
[2] https://www.ncbi.nlm.nih.gov/pubmed/30600821
[3] https://www.ncbi.nlm.nih.gov/pubmed/30503797
[4] https://www.ncbi.nlm.nih.gov/pubmed/29527831
[5] https://www.ncbi.nlm.nih.gov/pubmed/29444261
[6] https://www.ncbi.nlm.nih.gov/pubmed/29491216
[7] https://www.ncbi.nlm.nih.gov/pubmed/29785666
[8] https://www.ncbi.nlm.nih.gov/pubmed/29334634